Metal working lubricant



United States Patent 3,367,866 METAL WORKING LUBRICANT George R. Cook, Arlington Heights, Allan A. Manteuffel, Crystal Lake, and Joseph B. Stucker, Des Plaines, Ill., assignors to Union Oil Company of California, Los Angeles, Calif., a corporation of California No Drawing. Filed Nov. 26, 1965, Ser. No. 510,093

11 Claims. (Cl. 252-333 ABSTRACT OF THE DISCLOSURE The invention relates to a metal working lubricant composition comprising (1) a lubricating oil base consisting of an aromatic extract obtained by solvent extraction of a mineral oil, (2) about to by weight of chlorinated paraflin and (3) an amount of an alkanol amine sufiicient to neutralize the hydrolyzable chlorine of the chlorinated paraflin.

The present invention pertains to lubricants, especially those intended for metal working applications of all kinds and particularly metal drawing. The invention is particularly concerned with a lubricating composition which is relatively noncorrosive and which permits drawing of aluminum, cold rolled steel, stainless steel and other metals and alloys under severe conditions while leaving the surface of the formed metal parts receptive, after a simple washing procedure, to other operations that may be performed thereon such as painting, enameling and porcelain- 12mg.

The prior art has heretofore suggested the addition of specific additives to lubricants for securing particular properties. Such additives include compounds added to minimize metal to metal contact and the resulting damage to metal under extreme conditions of pressure. Representative types of such compounds include sulphur compounds, halogen compounds, and various other compounds and substances in which the sulphur and halogen elements are combined.

In very severe operations such as in the severe drawing of diificultly workable metals, chlorinated paraffins and chlorinated sperm oil having chlorine contents of about -70 wt. percent have been used with some success. However, the side eifects such as corrosion, the dii'ficulty in removing the drawing compounds and the relatively high cost of the compounds do not provide metal workers with a completely satisfactory drawing compound.

While the prior art has suggested various types of additives for various purposes, it appears that the prior art has not thoroughly investigated the basic characteristics of the lubricating medium to which the additives are added.

It has now been unexpectedly found that a. specific type of lubricating medium to which has been added certain specific additives performs as well or better than those chlorinated hydrocarbons which have been utilized under severe conditions but which have produced severe adverse side effects. Basically, the lubricating composition of this invention comprises a major proportion of a petroleum lubricating oil obtained from the solvent extraction of mineral oil and characterized as having a high aromatic "ice content and a viscosity in the range of 25,000 SUS at 100 F. to which has been added about 10 to 48 wt. percent of a chlorinated parafiin having a chlorine content of at least 40% by wt. and a sufficient amount of a lower molecular weight alkanol amine to neutralize the hydrolyzable chlorine of the chlorinated parafiln. The novel lubricating composition not only provides suitable lubrication for the most severe drawing applications, but also is free of the severe corrosion problems encountered in the use of prior art compounds and lowers the cost of deep-drawing operations. In other embodiments, the use of certain other additives causes the formed metal parts to be adequately protected from corrosion with a protective film which is readily removable by simple alkali Washing procedures.

It is an object of the present invention to provide a compounded lubricant having unusual properties for metal cutting, metal rolling, and particularly for the draw ng of oxygen-process steel, aluminum, and various other metal alloys.

It is a further object of this invention to provide a metal lubricating composition which is noncorrosive to the metal being drawn.

It is a further object of this invention to provide a metal lubricating composition which imparts a protective film to the formed metal parts in drawing operation which is readily removable.

These and other objects of the invention will become apparent from reading the hereinafter following commentary.

The lubricating oil-base media of our novel composition are well known byproducts of the solvent extraction of mineral lubricating oils and are adequately described as those aromatic materials separated from mineral lubrieating oils. and their fractions, i.e., those aromatics obtained in the manufacturing and refining of neutral oils and bright stocks during treatment with a selective solvent designed to extract the predominantly aromatic materials from the paraiiinic materials. Solvent extracts resulting from the treatment of mineral lubricating oils for the purposes of separating non-aromatic hydrocarbons from the aromatic hydrocarbons may be used, and are a necessary component of the overall composition.

Since the general process of refining mineral lubricating oils in which solvent extracts are obtained is well known, it is only necessary for present purposes to describe a typical procedure for obtaining same and give some examples by way of illustration.

In a typical operation, desalted crude oil is first charged to a distillation unit where straight-run gasoline, two grades of naphtha, kerosine, and virgin distillate are taken off, leaving a reduced crude residue. The reduced crude is continuously charged to a vacuum distillation unit where lubricating oil distillates are taken oif as side streams, a light distillate is taken off as: overhead, and a residuum is withdrawn from the bottom of the tower. The residuum is charged to a propane-deasphalting unit wherein desirable lubricating oil constituents are dissolved in propane and the insoluble asphaltic materials are separated out. A typical vacuum residuum charge to the propane-deasphalting unit may have an API gravity of 12.9"; viscosity SUS at 210 F. of 1249; flash 585 F.; fire 650 F.; percent carbon residue of 13.9 weight percent, and may be black in color. The deasphalted oil may have an API gravity of 21.5 to 21.8; viscosity, SUS, 210 F. of 165-175; NPA color 6-7; flash 575 F.; fire 640 F.; and percent carbon residue of 1.7-2.0. The deasphalted oil and various lubricating oil distillates from the reduced crude are subjected to solvent extraction for the separation of aromatic from non-aromatic constituents prior to use. The refined oil, or raflinate, from the extraction processes is used per se, or as blending stock, for lubricating oils, and the solvent extract, predominating in complex aromatic constituents, is distinctively useful in accordance with this invention.

For example, a crude oil from an East Texas field with an API gravity of 33.1 was topped to remove such light fractions as gasoline, naphtha, kerosine, and a light lubricating distillate. The vacuum residue had a viscosity of 1251 SUS at 210 F., 2.2 percent sulfur, and an API gravity of 12.6. After propane deasphalting, the oil had a viscosity of 174 SUS at 210 F., and an API gravity of 21.7". This deasphalted oil was treated with phenol to produce a raffinate from which an aviation lubricating oil could be prepared. The oil extracted by phenol treatment, after removal of phenol, is ready for use as the main substituent in the composition in accordance with this invention.

Solvents other than phenol may be used to obtain the extraction product used in accordance with this invention. For example, liquid sulfur dioxide, nitrobenzene, Chlorex, chlorophenol, trichloroethylene, cresylic acid, pyridine, furfural, or the Duo-Sol solution (comprising liquid propane and cresol) may be used. When using phenol, it is possible to vary the characteristics of the extract and rafiinate products considerably by adjustment of the amount of water present. A raffinate of relatively low viscosity index can be obtained by using a water solution of phenol during the extraction, and a raffinate of high viscosity index can be obtained by using anhydrous phenol. Following are the physical characteristics of typical extract products, from lubricating oil stocks derived from various crude oils and other source hydrocarbon materials, which may be used in accordance with this invention.

Characteristic: Range of value Gravity, API 7.015.0. Gravity, sp., 380/155 C. 09550-1000. Viscosity, SUS, @100 F. 100-25,000 (ext.). Viscosity, SUS, @130 F 60.10,000. Viscosity, SUS, @210 F -1500. Viscosity index -101-+39. Pour point (max), F +35-100. Color, NPA +.1-5D. Molecular weight, average 300-750. Boiling point (initial), F. 300-1000. Boiling point (end), F 400-1200. Sulfur, percent, wt 1.9-4.5. Sulfur compounds, percent wt. 20-50. Aromatics and thio compounds,

percent, wt 50-90. Thio compounds, percent, wt. 14-40. Neutral aromatic hydrocarbons,

percent, wt 40-51. Av. No. rings/means arom.

mol 1.7-5.0. H/C Wt. ratio 0.l160.136. H/C atom ratio, whole sample 1.383-1.622. H/ C atom ratio, aromatic portion 1.289-1.500.

The gravities of the extracts in general increase with increase in the viscosity of the rafiinate at a constant viscosity index. Stated otherwise, the gravities of these extracts increase with decrease in viscosity. For the pro duction of i5 V.I. neutral oils, the viscosities of the extracts increase with increase in stated viscosities of the neutral oils (raffinates). The pour points of extracts are high and are affected by changes in the depth of extraction. The sulfur contents are also affected by the depth of extraction. The solvent extracts are characterized by containing aromatic and sulfur compounds in the range Nearest empirical formula TABLE I.-SOUROES AND PHYSICAL CHARACTERISTICS OF SOLVENT EXTRACTS Ext. Crude API Sp. Gr. Vis./ Vis./ Vis.] F. F. Iodine Percent Percent N 0. Source Solvent Grav. at 10 100 210 V.I. Pour Flash Fire No. Sulfur F. F. F. (W115) East Tex.- 11.1 23,319 4,750 282 15. 4 15, 000 285 12.6 36, 410 4, 310 310. 1 14. 6 19, 500 4, 305 313 15. 4 32, 500 372 13. 7 25, 000 5, 400 355 8. 6 145, 000 19, 000 616 10. 5 12, 676 2, 514 172. 1 10. 2 371 Furtural 13. 0 1, 500 Chlorex 12. 2 1, 365 Nitro-benzene 10. 0 500 Extract No. 41 was obtained in the production of 85 Vis. neutral, has an average molecular weight of 300, and contained 76.8% aromatics (by the silica gel procedure).

Extract N o. 42 was obtained in the production of Vis. Bright Stock, has an average molecular weight of 590, and contained 86% arematics, 14% saturates, 86.2% carbon, 11.4% hydrogen, and averaged 3.3 aromatic rings per aromatic molecule.

Extract No. 43 was obtained in the production of 170 Vis. neutral,

has an average molecular weight 01 340, contained 84.1% aromatics. 15.9 saturates, 86.4% carbon, 10.7% hydrogen and averaged 2.7 aromatic rings per aromatic molecule.

Extract No. 44 was obtained in the production of 200 Vis. neutral, has an average molecular weight of 340, contained 87% aromatics, and 13% saturates.

Extract No. 45 was obtained in the production of Vis. Bright Stock, contained 92% aromatics and 8% saturates.

of 70-90%, the remainder being principally saturates, or material behaving as saturates, together with a minor proportion of from 3.0 to 6.0% of organic acids. The organic acids present are not susceptible to extraction by the use of aqueous strong caustic because of emulsion formation. Very little asphaltic material is present in solvent extracts and they contain no material volatile at room temperatures.

The materials shown in Tables I and II are merely illustrative and the invention is not to be limited thereby.

The novel metal lubricating composition, in addition to the aforedescribed petroleum lubricating oil component, necessitates two other components in order to gain the attributes described in the objects of the invention. The other two essential ingredients are a chlorinated parafiin and a low molecular weight alkanol amine. The chlorinated parafi'in is a chlorinated wax such as a chlorinated petroleum wax either of the paralfin or micro-crystalline type. The chlorinated wax, however, may vary quite widely provided it has a minimum chlorine content of 40% by wt. Such a wax is known by the proprietary name Chlorowax 40, marketed by Diamond Alkali Co. wherein the properties and characteristics of the chlorinated paraflin are those described in the Condensed Chemical Dictionary, th Ed., Reinhold.

Triethanolamine is a preferred low-molecular-weight alkanol amine, as it is available commercially. The product on the market usually consists of a mixture of mono-, di-, and triethanol amine with some water, but it is to be understood that pure triethanol amine may be used if desired. Also, other mono-, diand trialkanol amines and their mixtures may be used, for instance, propanol, butanol, pentanol, etc., amines wherein the alkanol portion has from 1-8 carbon atoms. It is important, in order to gain the attributes of this invention, that there be a sufficient amount of low molecular weight alkanol amine present in the composition to neutralize or combine with the hydrolyzable chlorine present in the composition in the form of the chlorinated paraffin. Thisamount will generally be within the range of 0.5 to 6 wt. percent, with a preferred amount of 1.6 wt. percent. A satisfactory commercially available alkanol amine is that available from the Dow Chemical Co. which has the following composition:

Triethanol amine 85% minimum.

Diethanol amine 15% maximum.

Monoethanol amine 0.5% maximum.

Water 0.20% maximum.

In addition to the foregoing three necessary components of the metal lubricating composition, it may be desirable, for an improved lubricant which provides a corrosion-protective film to the drawn metal parts, to add small amounts of a compound which comprises a mixture of aliphatic, oxygen-containing compounds of petroleum origin, obtained by controlled oxidation of hydrocarbons or mixtures thereof (such as the hydrocarbons occuring in, or associated with, petroleum oils) in liquid phase, at an elevated temperature and under super-atmospheric pressure. These aliphatic compounds contain mixtures of substantial quantities of alcohols, ketones, lactones, and esters, together with some unoxidized hydrocarbon. The method of obtaining these oxygen-containing aliphatic compounds and the compositions thereof are described in US. patents 1,690,768; 1,690,769; 1,863,004; and others issued to A. W. Burwell. Products of the type described in these patents are marketed under the tradename of Alox compounds, compounds marketed as Alox 152," Alox 315, and Alox 600 being especially well suited for this purpose. These aliphatic, oxygenated hydrocarbons will be referred to hereinafter in this specification and the appended claims as petroleum oxidation products.

Alox 600," a proprietary product available from the Alox Corporation, typically has the following characteristics:

The amount of the petroleum oxidation products added to the composition is normally that amount which will prevent severe corrosion of the drawn metal parts. Ordinarily, the effective amount ranges in the vicinity of 0.5 to 10 wt. percent of the composition, with a preferred value of 2 wt. percent having been found effective under most conditions.

To provide for the proper level of emulsification, and to facilitate the removal of the protective coating from the drawn metal parts, it is desirable to incorporate a sulfonate in the composition as the primary emulsifying agent. The sulfonate, and emulsification agent, permits cleaning of the drawn metal parts by simple washing with water or alkaline solutions. The sulfonates are generally any of those known in the art which have detergentemulsifier properties. Suitable sul-fonates include the alkali and alkaline earth metal alkaryl sulfonates formed by alkylating benzene, toluene, xylene, cumene, naphthalene, alkyl naphthalene, diphenyl, alkyldiphenyl, and the halogen derivatives such as chlorobenzene, chlorotoluene, chloronaphthalene, followed by sulfonation and by neutralization with an alkali or alkaline earth metal base. The alkylation may be accomplished under the influence of a catalyst with alkylating agents containing from about 3 to more than 20 carbon atoms, such as, for example, haloparaifins; olefins, as from the dehydrohalogenation of haloparaffins; polyolefins such as, for example, polymers from ethylene, propylene and butylene; alkylsulfates; aliphatic alcohols; and others. The catalyst may be sulf-uric acid, hydrochloric acid, phosphorus-containing catalysts, aluminum chloride, or boron fluoride, alone or with activators such as hydrogen fluoride or hydrogen chloride. Other hydrocarbons that may be used are raw petroleum distillates or fractions, including those that have or have not been subjected to selective solvent action. In general, the alkaryl sulfonate or other sulfonates shou-ld be oil soluble and for that reason suitable sulfonates are those containing from about 20 to about 30 carbon atoms. Suitable commercially available su-lfonates are those such as Morco 62-M, sodium sulfonate a proprietary product of the Mineral Oil Refining Company, and Petronate H-L, a sodium sulfonate proprietary product of the Sonneborn Chemical and Refining Company. The sulfonate may also be one known as mahogany sulfonate and in addition encompasses the sulfonic acid derivatives disclosed in Sulfonic Derivatives as Lubricating Additives, by George D. Pritzker appearing in National Petroleum News, vol. 37, No. 40, pages R-793 to R-800. The amount of sulfonate used will generally fall Within the range of 7 to 25 wt. percent of the total composition, with a value of 10 wt. percent being effective under most circumstances.

The preferred formulation of our metal lubricating composition, in addition to the foregoing also contains a secondary emulsifier system. An example of a suitable secondary emulsifier which may be employed in conjunction with the composition of this invention is the alkali metal salt of various processed rosins and natural resins, including rosin acid, known in the art as alkali metal resinate. Sodium resinate, known under the tradename of Dresinate 81, has been found to be satisfactory as illustrative of the additive, since this salt imparts the desired characteristics to the metal lubricating composition. Emulsifiers of this nature are described in the brochure entitled Hercules Dresinates, published by the Hercules Powder Company (1954). Suitable emulsifiers may be are merely added and stirred to obtain a homogeneous dispersion of the additives throughout the predominantly aromatic lubricating oil fraction. In most instances, temperatures which are slightly higher than ambient will facilitate prepared from organic acids or organic a id mixtures, transfer and solution of the additives in the main lubri- The characteristics of a particular emulsifier will vary, of catlngoil fraction. course, but merely for illustrative purposes the following Whl the Illustrative exampl s glven In Table 11 W11 is a compilation of the characteristics of Dresinate 81 Suffice under most mfital dfflwlng cond1.t1 OnSa the Preferred which is a sodium resinate: formulation or lubricating oil composition has the broad characteristics as enumerated in Table III. Properties Test Procedure Typical Tests TABLE III Vis. in SUS at100 F ASTM D 44MB..- 10. 60010, 700 P f d Lubricant; W t v 1. t 6 12-13 Green) AOCS L 32l.55. 14-16 Viscosity at 100 F., 535 to 765 S.S.U; Pour Point, i i ii t rear 5 Sifii 8 iii 15 {I Tzgalpercentflfi 87.0/88.0 Viscosity at 210 F., 57 to 64 S.S.U; Flash Point,

400 F. Ti-ace Fe. Gravity, API at 60 F., 9.2 to 10.5; Fire Point,

425 F. The secondary emulsifier will generally comprise about S ifi Gravity at 60/60 R, 0.9965 to 1.0028; 2.5 to 10 wt. percent of the metal lubricant, with a pre- C0101, ASTM, 1,4.0 Dil, ferred value of 5 wt. percent of the composition being Weight per GaL at 0 F 299 to g 37 1 h1 effective for the intended purposes. ri Content, 8.0% (wt) To illustrate several of the metal drawing compounds A id N ASTM D 664, 33; W t Content, 1.2% formulated in accordance with the invention, there appear L) in Table II, hereinafter following, suitable compositions B N ASTM D 664, 9,3; sulfated Ash, 2.1% which have been found to be effective metal lubricants, e) with Blend 2 being superior to the other designated formulations. The various components, some of which are re- The examples given hereinabove are supplied to illusferred to by tradename, have been adequately defined and trate the invention without in any way limiting the scope disclosed herein, and the predominant lubricating oil of the invention. The only limitations intended are those proportion, i.e., Extract 36 and Extract 41, are those exfound in the attached claims. tracts which may be found in Table I. The pale oil utilized The embodiments of this invention in which an excluin Blend 3 is a Gulf Coast, acid-refined neutral having the sive property or privilege is claimed are defined as follows: following characteristics: 1. A metal lubricating composition comprising:

(a) a major proportion of a petroleum lubricating oil API gravity 21.5/24.5. obtained from the solvent extraction of mineral oil COC flash, F 310 min. and characterized as having a high aromatic content COC fire, F 350 min. and a viscosity in the range of 10025,000 SUS at SUS @100 F 100-115. 100 F.; SUS @210 F 36-38. (b) about 10 to 35% by weight of a chlorinated paraf- ASTM pour, F 25 max. fin having a chlorine content of at least 40% by Color 2 max. weight; and Aniline point, F 152. (c) a sufiicient amount of a low molecular weight alka- TABLE II Blend 3 (A Blend 4 (A Blend 1 Blend 2 Low Vis., High Viscosity Formula Formula Low Pour Product) Product) Formula Formula Composition by Weight, percent:

Alox 600 2. 00 2. 00 Chlorowax 40 20. 0 19. 97 20. 00 Dresinate s1"- 10. 0 4. 99 5. 00 MORCO 62-M or Petronate 12. 0 9. 98 10.00 Triethanolamine- 2. 6 1. 57 1. 60 Extract 36 20.30 Extract 41 61. 49 4.1. 10

Pale Oil Properties:

Viscosity at 100 F., S. 792. 6 764. 3 1579. 8 Viscosity at 210 F., s 02. 9 04. 4 s5. 4 Pour Point, F +40 +40 Flash Point, 0.0.0., 400 400 Fire Point, 0.0.0., 425 425 Color, ASTM L6. 5 1 L4. 0 1 L5. 0 Chlorine Content, Wt. percent. 8.0 8. 0 8.0 Water Content, V01 percent... 1. 5 1.2 0.7 Ash as Sulfate, Wt percent 2. 1 2.1 Acid No., ASIM D 664--- 3. 4 3. 3 1. s 3. 7 Base No. AS'IM D 664- 12. 3 9. 3 10.0 9.8 API Gravity at 8. 5 9. 2 12. e s. s Specific Gravity at 60l60 1. 0107 1. 0057 0. 9820 1. 0100 Weight per Gallon at 60 F., lbs- 8.4.8 8.376 8. 178 8.418

Dil.

The method of compounding the novel lubricating comnol amine to neutralize the hydrolyzable chlorine of position is not unique or critical. The oil fraction is merely said chlorinated parafifin. added to a compounding kettle and the other components 2. A composition according to claim 1 wherein said Gravity, API 7.0-15.0 Viscosity, SUS, at 130 F 60-19,000 Viscosity, SUS, at 210 F 50-1500 Viscosity index -110-+39 Pour point, F. |25-100 Molecular wt., average (above 300) 300-750 Sulfur, percent, wt. 1.9-4.5 Average No. of rings/mean aromatic molecule 1.7-5.0

3. A composition according to claim 2 which additionally comprises about:

(a) 0.5 to 10.0 wt. percent of the composition of a mixture of saturated aliphatic, oxygen-containing compounds including alkyl esters, lactones, ketones, alcohols and alcohol-ketones, said mixture being obtained by the partial oxidation of petroleum hydrocarbons;

(b) 7 to 25 wt. percent of the composition of alkali metal salt of C -C sulfonic acids; and

(c) 2.5 to 10 wt. percent of the composition of an alkali metal resinate.

4. A composition according to claim 3 in which said alkali metal is sodium.

5. A composition according to claim 4 in which said mixture obtained by the partial oxidation of petroleum hydrocarbons has the following general characteristics:

Range of values Moi. wt 545-575 6. A composition in accordance with claim 5 in which said alkali metal resinate has the following general characteristics:

Viscosity, SUS at 100 F. 10,600-10,700 H O Content, vol. percent 12-13 Acid No 14-16 Sulfated Ash, wt. percent 8.7-9.0

7. A composition in accordance with claim 6 in which said low molecular weight alkanol amine is primarily triethanol amine.

8. A composition according to claim 4 in which said lubricating oil has about the following characteristics:

Gravity, API 17.6

Viscosity, SUS, at 100 F. 154 Viscosity, SUS, at 130 F. 80 Viscosity, SUS, at 210 F. 41 Viscosity index 11 10 Pour point, F. +30 Flash point, F. 400 Fire point, F 435 Sulfur, percent, wt. 2.0

and is obtained in the production of VIS neutral, has an average molecular weight of 300 and contains about 77% aromatics as determined by the silica gel procedure.

9. A composition in accordance with claim 8 in which said chlorinated paraflin is a chlorinated paraffin wax having 40% by weight of chlorine.

10. A composition according to claim 9 wherein said alkali metal salt has about the following general characteristics:

Na sulfonates, wt. percent 62 Mineral oil, wt. percent 33 Water, wt. percent 5 Free NaOH, wt. percent 0.1 Na carboxylate, wt. percent 0.1 Specific gravity, 25/25 C 1.015 Sulfated ash, wt. percent 9.8 Base No. (D664) 4 Vis. SUS at 210 F 2500 Pour point, F. +50

11. A composition in accordance with claim 10 which has about the following general characteristics:

Viscosity, SSU at F. 792.6 Viscosity, SSU at 210 F. 62.9 Pour point, F. +40 Flash point, C.O.C., F. 400 Fire point, C.O.C., F. 425 Color ASTM 1.6.5 Chlorine content, wt. percent 8.0 H 0 content, vol. percent 1.5 Ash as sulfate, wt. percent 2.1 Acid No. 3.4 Base No. 12.3 Gravity, API at 60 F. 8.5 Spr. gravity at 60/60 F 1.0107

References Cited UNITED STATES PATENTS 1,863,004 6/1932 Burwell 25255 1,884,749 10/1932 Kocour 252-9 2,126,128 8/1938 Montgomery 252-9 2,529,188 11/1950 Rocchini et al 252-58 X 2,626,240 1/1953 Deutser et a1. 252-49.5 X 2,825,693 3/1958 Beaubien et a1. 25249.3 X

OTHER REFERENCES Bastian-Metalworking Lubricants-published by McGraw-Hill, New York, N.Y. first edition, 1951, pp. 12-13 most pertinent.

DANIEL E. WYMAN, Primary Examiner. PATRICK P. GARVIN, Examiner. 

